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Accceptable Tolerances?

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  • punkrockdad2
    While squaring my machine up I was wondering about what are acceptable tolerances. I suppose experience will give me a greater understanding of what I should
    Message 1 of 16 , Mar 1, 2009
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      While squaring my machine up I was wondering about what are acceptable
      tolerances. I suppose experience will give me a greater understanding
      of what I should be targeting for a particular job but I'm new on this
      machining marlarky so I'd appreciate everybody elses take on it. I
      could be there all day/week/year/millennia looking for zero. Its
      getting all Buddhist!

      I'm metric (too young for that imperial stuff).

      So should I be happy with 0.02mm backlash in the z axis? 0.1mm run out
      over 100mm on the A axis? 0.08mm in the X and 0.08mm on the Y?

      Its a taig cnc mill btw.
    • Steve Blackmore
      ... Taig s advertised mechanical resolution figures are 0.0005 inch or 0.0127mm. I d settle for 0.02 all round, I think you be hard pressed to better that.
      Message 2 of 16 , Mar 1, 2009
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        On Sun, 01 Mar 2009 08:52:37 -0000, you wrote:

        >While squaring my machine up I was wondering about what are acceptable
        >tolerances. I suppose experience will give me a greater understanding
        >of what I should be targeting for a particular job but I'm new on this
        >machining marlarky so I'd appreciate everybody elses take on it. I
        >could be there all day/week/year/millennia looking for zero. Its
        >getting all Buddhist!
        >
        >I'm metric (too young for that imperial stuff).
        >
        >So should I be happy with 0.02mm backlash in the z axis? 0.1mm run out
        >over 100mm on the A axis? 0.08mm in the X and 0.08mm on the Y?

        Taig's advertised mechanical resolution figures are 0.0005 inch or
        0.0127mm.

        I'd settle for 0.02 all round, I think you be hard pressed to better
        that.

        Having said that, it depends what your making. If your making decorative
        parts, a .1mm here or there may not matter, if you were boring out the
        cylinder for a small steam engine it would matter a great deal.

        Steve Blackmore
        --
      • Stan Stocker
        ... Greetings, Unless you are using ball screws, which can have zero backlash, you must have SOME backlash. Just the nature of threaded couplings. In
        Message 3 of 16 , Mar 1, 2009
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          punkrockdad2 wrote:
          > While squaring my machine up I was wondering about what are acceptable
          > tolerances. I suppose experience will give me a greater understanding
          > of what I should be targeting for a particular job but I'm new on this
          > machining marlarky so I'd appreciate everybody elses take on it. I
          > could be there all day/week/year/millennia looking for zero. Its
          > getting all Buddhist!
          >
          > I'm metric (too young for that imperial stuff).
          >
          > So should I be happy with 0.02mm backlash in the z axis? 0.1mm run out
          > over 100mm on the A axis? 0.08mm in the X and 0.08mm on the Y?
          >
          > Its a taig cnc mill btw.
          >
          >
          Greetings,

          Unless you are using ball screws, which can have zero backlash, you must
          have SOME backlash. Just the nature of threaded couplings. In general,
          0.1mm backlash is a reasonable amount. Much more and things can get
          silly sloppy, but much tighter than that and you increase the wear on
          the leadscrew and nut.

          Most of the time I set up for a smooth operation over the entire range
          on a machine, which seems to be around 3 to 5 thousandths of an inch.
          Thats around 0.1mm for the imperially challenged folks :-). Any tighter
          and it loosens up to around this amount on it's own in the areas where
          the majority of work is done. Once this happens several times, the
          machine has loose and tight spots and the compromises extend to an even
          larger range. Any looser and the slide or table tends to be able to
          vibrate unless the gibs are snugged extra. Naturally, snugging the gibs
          increases the load on the lead screws, and the whole silly cycle goes
          round again.

          Chasing perfection in machine tools is a distraction from getting on
          with the work in hand and life in general. Works well is fine and
          dandy. Nirvana might not be absolute perfection, it could be happiness
          with pretty darn good.

          And I'm actually kidding about the imperially challenged, I use both
          systems daily as I fix clocks for a living. You haven't lived until you
          put a 0.026 inch pivot wire in a 1/8 inch arbor, and bush the bore with
          a 1.9mm high, 2.7mm OD, 0.4mm ID bushing! Broach to running fit using
          tapered British Stubbs gauge numbered reamers and burnish the bore with
          a French wire number smoothing broach to finish. Gee I LOVE standards,
          each and every one of them.

          Cheers,
          Stan
        • punkrockdad2
          Are you hitting 0.02mm across all the travel steve? I m only working in a 100mm x envelope. I m using mach3 for control and was wondering about backlash
          Message 4 of 16 , Mar 1, 2009
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            Are you hitting 0.02mm across all the travel steve? I'm only working
            in a 100mm x envelope. I'm using mach3 for control and was wondering
            about backlash compensation?

            There seems to be a few in favour and a few that think its useless and
            the work of the devil, but with no real reasons why...

            Talk about scale? I'm grinding single lip cutters under a microscope
            to 0.04mm.


            --- In taigtools@yahoogroups.com, Stan Stocker <skstocker@...> wrote:
            >
            > punkrockdad2 wrote:
            > > While squaring my machine up I was wondering about what are acceptable
            > > tolerances. I suppose experience will give me a greater understanding
            > > of what I should be targeting for a particular job but I'm new on this
            > > machining marlarky so I'd appreciate everybody elses take on it. I
            > > could be there all day/week/year/millennia looking for zero. Its
            > > getting all Buddhist!
            > >
            > > I'm metric (too young for that imperial stuff).
            > >
            > > So should I be happy with 0.02mm backlash in the z axis? 0.1mm run out
            > > over 100mm on the A axis? 0.08mm in the X and 0.08mm on the Y?
            > >
            > > Its a taig cnc mill btw.
            > >
            > >
            > Greetings,
            >
            > Unless you are using ball screws, which can have zero backlash, you
            must
            > have SOME backlash. Just the nature of threaded couplings. In
            general,
            > 0.1mm backlash is a reasonable amount. Much more and things can get
            > silly sloppy, but much tighter than that and you increase the wear on
            > the leadscrew and nut.
            >
            > Most of the time I set up for a smooth operation over the entire range
            > on a machine, which seems to be around 3 to 5 thousandths of an inch.
            > Thats around 0.1mm for the imperially challenged folks :-). Any
            tighter
            > and it loosens up to around this amount on it's own in the areas where
            > the majority of work is done. Once this happens several times, the
            > machine has loose and tight spots and the compromises extend to an even
            > larger range. Any looser and the slide or table tends to be able to
            > vibrate unless the gibs are snugged extra. Naturally, snugging the
            gibs
            > increases the load on the lead screws, and the whole silly cycle goes
            > round again.
            >
            > Chasing perfection in machine tools is a distraction from getting on
            > with the work in hand and life in general. Works well is fine and
            > dandy. Nirvana might not be absolute perfection, it could be happiness
            > with pretty darn good.
            >
            > And I'm actually kidding about the imperially challenged, I use both
            > systems daily as I fix clocks for a living. You haven't lived until
            you
            > put a 0.026 inch pivot wire in a 1/8 inch arbor, and bush the bore with
            > a 1.9mm high, 2.7mm OD, 0.4mm ID bushing! Broach to running fit using
            > tapered British Stubbs gauge numbered reamers and burnish the bore with
            > a French wire number smoothing broach to finish. Gee I LOVE standards,
            > each and every one of them.
            >
            > Cheers,
            > Stan
            >
          • Brian D. W.
            So how difficult would it be to change out the Taig lead screws with a set of ballscrews?   After looking at Taigs specs on their mini mill, I m inclined to
            Message 5 of 16 , Mar 1, 2009
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              So how difficult would it be to change out the Taig lead screws with a set of ballscrews?   After looking at Taigs specs on their mini mill, I'm inclined to think that it's probably as good as you can get it with factory parts.  Has anyone endeavored to pursue more accuracy and precision?

              Brian

              --- On Sun, 3/1/09, punkrockdad2 <warrenpe@...> wrote:
              From: punkrockdad2 <warrenpe@...>
              Subject: [taigtools] Re: Accceptable Tolerances?
              To: taigtools@yahoogroups.com
              Date: Sunday, March 1, 2009, 8:58 AM












              Are you hitting 0.02mm across all the travel steve? I'm only working

              in a 100mm x envelope. I'm using mach3 for control and was wondering

              about backlash compensation?



              There seems to be a few in favour and a few that think its useless and

              the work of the devil, but with no real reasons why...



              Talk about scale? I'm grinding single lip cutters under a microscope

              to 0.04mm.



              --- In taigtools@yahoogrou ps.com, Stan Stocker <skstocker@. ..> wrote:

              >

              > punkrockdad2 wrote:

              > > While squaring my machine up I was wondering about what are acceptable

              > > tolerances. I suppose experience will give me a greater understanding

              > > of what I should be targeting for a particular job but I'm new on this

              > > machining marlarky so I'd appreciate everybody elses take on it. I

              > > could be there all day/week/year/ millennia looking for zero. Its

              > > getting all Buddhist!

              > >

              > > I'm metric (too young for that imperial stuff).

              > >

              > > So should I be happy with 0.02mm backlash in the z axis? 0.1mm run out

              > > over 100mm on the A axis? 0.08mm in the X and 0.08mm on the Y?

              > >

              > > Its a taig cnc mill btw.

              > >

              > >

              > Greetings,

              >

              > Unless you are using ball screws, which can have zero backlash, you

              must

              > have SOME backlash. Just the nature of threaded couplings. In

              general,

              > 0.1mm backlash is a reasonable amount. Much more and things can get

              > silly sloppy, but much tighter than that and you increase the wear on

              > the leadscrew and nut.

              >

              > Most of the time I set up for a smooth operation over the entire range

              > on a machine, which seems to be around 3 to 5 thousandths of an inch.

              > Thats around 0.1mm for the imperially challenged folks :-). Any

              tighter

              > and it loosens up to around this amount on it's own in the areas where

              > the majority of work is done. Once this happens several times, the

              > machine has loose and tight spots and the compromises extend to an even

              > larger range. Any looser and the slide or table tends to be able to

              > vibrate unless the gibs are snugged extra. Naturally, snugging the

              gibs

              > increases the load on the lead screws, and the whole silly cycle goes

              > round again.

              >

              > Chasing perfection in machine tools is a distraction from getting on

              > with the work in hand and life in general. Works well is fine and

              > dandy. Nirvana might not be absolute perfection, it could be happiness

              > with pretty darn good.

              >

              > And I'm actually kidding about the imperially challenged, I use both

              > systems daily as I fix clocks for a living. You haven't lived until

              you

              > put a 0.026 inch pivot wire in a 1/8 inch arbor, and bush the bore with

              > a 1.9mm high, 2.7mm OD, 0.4mm ID bushing! Broach to running fit using

              > tapered British Stubbs gauge numbered reamers and burnish the bore with

              > a French wire number smoothing broach to finish. Gee I LOVE standards,

              > each and every one of them.

              >

              > Cheers,

              > Stan

              >































              [Non-text portions of this message have been removed]
            • Steve Blackmore
              ... Less than 0.01mm, but I m not using a Taig these days. ... Never try to fudge with software what you can fix mechanically ;) Main reason against is it only
              Message 6 of 16 , Mar 1, 2009
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                On Sun, 01 Mar 2009 13:58:53 -0000, you wrote:

                >Are you hitting 0.02mm across all the travel steve? I'm only working
                >in a 100mm x envelope. I'm using mach3 for control and was wondering
                >about backlash compensation?

                Less than 0.01mm, but I'm not using a Taig these days.

                >There seems to be a few in favour and a few that think its useless and
                >the work of the devil, but with no real reasons why...

                Never try to fudge with software what you can fix mechanically ;)

                Main reason against is it only applies the backlash correction when the
                move stops.

                Steve Blackmore
                --
              • punkrockdad2
                ... so if i m only moving in a straight line in x or y i should be ok?
                Message 7 of 16 , Mar 1, 2009
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                  > Main reason against is it only applies the backlash correction when the
                  > move stops.

                  so if i'm only moving in a straight line in x or y i should be ok?
                • punkrockdad2
                  ... a set of ballscrews?   After looking at Taigs specs on their mini mill, I m inclined to think that it s probably as good as you can get it with factory
                  Message 8 of 16 , Mar 1, 2009
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                    > So how difficult would it be to change out the Taig lead screws with
                    a set of ballscrews?   After looking at Taigs specs on their mini
                    mill, I'm inclined to think that it's probably as good as you can get
                    it with factory parts.  Has anyone endeavored to pursue more accuracy
                    and precision?


                    Well its funny you should mention that. Its what caused me to ask the
                    question in the first place. Spending a huge amount of time
                    maintaining tolerances is counter productive for me. I have achieved
                    better numbers in the past but maintaining them with the level of
                    usage and speed I prefer is taking up alot of time. Even with home
                    limits and fixture offsets set up I find the repeatability drifts and
                    I end up manually rechecking alignment.

                    There are a few options I'm looking at.

                    1. Replacing the present leadscrews with ballscrews. Seems the
                    consensus is that theres not enough room.

                    2. Exploring the Mach3 backlash compensation feature.

                    3. Buying into an off the shelf linear table with ballscrews /
                    antibacklash etc and replacing the entire taig table. Its looking
                    expensive.

                    4. Doing number 3 and adding the rest of the structure as well! ie
                    building a new mill. Long term project methinks!


                    Any suggestions / suppliers/ examples would be welcome...
                  • Brian D. W.
                    you know - I just signed on with this group in pursuit of maybe finding a Taig mill, because I was originally going to build a CNC mill/small gantry system.. 
                    Message 9 of 16 , Mar 1, 2009
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                      you know - I just signed on with this group in pursuit of maybe finding a Taig mill, because I was originally going to build a CNC mill/small gantry system..  After much research and digging, I had determined that I didn't really want to build a tool, rather I wanted to have a tool that I could build things with.  Tool building gets you into a whole different ball game - and quiet often it takes a lot of time.  I don't yet have a Taig mill, however, I don't think it would be impossible to retro-upgrade it with precision rail bearings and ballscrews?  THough, I'd take a guess that this option would probably involve some considerable modifications to the existing base.   I'm sure that there's folks out there/maybe in this group who've probably already fought the battle?..

                      Brian, 


                      --- On Sun, 3/1/09, punkrockdad2 <warrenpe@...> wrote:
                      From: punkrockdad2 <warrenpe@...>
                      Subject: [taigtools] Re: Accceptable Tolerances?
                      To: taigtools@yahoogroups.com
                      Date: Sunday, March 1, 2009, 1:20 PM














                      > So how difficult would it be to change out the Taig lead screws with

                      a set of ballscrews?   After looking at Taigs specs on their mini

                      mill, I'm inclined to think that it's probably as good as you can get

                      it with factory parts.  Has anyone endeavored to pursue more accuracy

                      and precision?



                      Well its funny you should mention that. Its what caused me to ask the

                      question in the first place. Spending a huge amount of time

                      maintaining tolerances is counter productive for me. I have achieved

                      better numbers in the past but maintaining them with the level of

                      usage and speed I prefer is taking up alot of time. Even with home

                      limits and fixture offsets set up I find the repeatability drifts and

                      I end up manually rechecking alignment.



                      There are a few options I'm looking at.



                      1. Replacing the present leadscrews with ballscrews. Seems the

                      consensus is that theres not enough room.



                      2. Exploring the Mach3 backlash compensation feature.



                      3. Buying into an off the shelf linear table with ballscrews /

                      antibacklash etc and replacing the entire taig table. Its looking

                      expensive.



                      4. Doing number 3 and adding the rest of the structure as well! ie

                      building a new mill. Long term project methinks!



                      Any suggestions / suppliers/ examples would be welcome...































                      [Non-text portions of this message have been removed]
                    • punkrockdad2
                      Heres the only ballscrew conversion I ve come across... http://www.chicobritish.org/CNC/
                      Message 10 of 16 , Mar 1, 2009
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                        Heres the only ballscrew conversion I've come across...

                        http://www.chicobritish.org/CNC/
                      • Andrew Werby
                        Brian D. W. bd_ski@yahoo.com bd_ski wrote: Date: Sun Mar 1, 2009 11:22 am ((PST)) you know - I just signed on with this group in pursuit of maybe finding a
                        Message 11 of 16 , Mar 1, 2009
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                          "Brian D. W." bd_ski@... bd_ski wrote:

                          Date: Sun Mar 1, 2009 11:22 am ((PST))

                          you know - I just signed on with this group in pursuit of maybe finding a Taig mill, because I was originally going to build a CNC mill/small gantry system.. After much research and digging, I had determined that I didn't really want to build a tool, rather I wanted to have a tool that I could build things with.

                          [Well, once you've got a mill working, you'll be in a better position to build another one...]

                          Tool building gets you into a whole different ball game - and quiet often it takes a lot of time.

                          [You've got that right - it's amazing how many little things can set back a project like that.]

                          I don't yet have a Taig mill, however

                          [Why don't you get one and use it for a while, and see how important that last little bit of precision really is to the projects you're doing? People often get hung up on these tolerance numbers, but it often turns out that they don't really matter in practical terms.]

                          I don't think it would be impossible to retro-upgrade it with precision rail bearings and ballscrews?

                          [While nothing's totally impossible, I suppose, this is something that's pretty impractical. The basic problem is that there are no precision ball-nuts available that would fit in the space provided in the Taig design. If you gouged out enough material to clear the nuts, the structure of the machine would be more than somewhat compromised.]

                          THough, I'd take a guess that this option would probably involve some considerable modifications to the existing base. I'm sure that there's folks out there/maybe in this group who've probably already fought the battle?..

                          Brian,

                          [Many have contemplated it, but few have attempted it, and even fewer have succeeded...]


                          punkrockdad2 <warrenpe@...> wrote:


                          > > So how difficult would it be to change out the Taig lead screws with
                          >

                          a set of ballscrews? After looking at Taigs specs on their mini

                          mill, I'm inclined to think that it's probably as good as you can get

                          it with factory parts. Has anyone endeavored to pursue more accuracy

                          and precision?

                          [The accuracy of the Taig screws is actually pretty good in terms of thread consistency. Most ballscrews have a lot more thread "drunkenness". It's true that ballscrews have less resistance, but that advantage goes away if the nuts get clogged, which they're prone to do. The main issue is backlash, which ballscrews are not immune to - the mere fact that it's a ballscrew does not preclude backlash; you either have to preload a couple of nuts against each other, or use oversized balls (which wear down) or get very expensive precision-ground preloaded screw-nut-bearing units.]



                          There are a few options I'm looking at.



                          1. Replacing the present leadscrews with ballscrews. Seems the

                          consensus is that theres not enough room.

                          [See above]



                          2. Exploring the Mach3 backlash compensation feature.

                          [Make sure you have an accurate measurement of the backlash, or this can cause more problems than it solves.]



                          3. Buying into an off the shelf linear table with ballscrews /

                          antibacklash etc and replacing the entire taig table. Its looking

                          expensive.

                          [Yup...]



                          4. Doing number 3 and adding the rest of the structure as well! ie

                          building a new mill. Long term project methinks!

                          [A Taig mill might come in handy for that...]



                          Any suggestions / suppliers/ examples would be welcome...


                          [Another alternative would be to install spring-loaded anti-backlash nuts. MaxNC uses them, and thus claims "zero backlash", but unfortunately they use the cheapest available nuts which compress too easily, giving back all the backlash and then some, and their plastic bodies tend to crumble in use. Also, since they don't bother providing bearing mounts for the screws, they float back and forth with the bearings of the motors. But there are better ones available, and Taig mills support their screws much better. Here are some sources: http://www.antibacklashnut.com/ ; http://www.nollinc.com/ ; http://tinyurl.com/dne6es ; http://kerkmotion.com/products/lead-screw/lead-screw-assemblies-overview.asp.

                          A2ZCNC has produced a retrofit kit for the Sherline mill based on a KerkMotion screw/nut combo that has been quite well-received, and they don't seem to have any more room in them than the Taig mills do. The most problematic parts of a retrofit like that would probably be machining the ends of the screws to fit in the Taig bearing mounts, and modifying the nut flanges to plug into the round holes that Taig provides for anchorage.]


                          Heres the only ballscrew conversion I've come across...

                          http://www.chicobritish.org/CNC/

                          [That's interesting, but I've never seen ball-nuts like that on the market. I suspect this fellow may have built them himself, but there's no narrative I could find to explain the pictures.]

                          Andrew Werby
                          www.computersculpture.com













                          [Non-text portions of this message have been removed]
                        • punkrockdad2
                          Looks like you ve thought alot of this through already andrew. I ve just found this chap whose thinking outside the box just a little... which I like ;)
                          Message 12 of 16 , Mar 1, 2009
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                            Looks like you've thought alot of this through already andrew.

                            I've just found this chap whose thinking outside the box just a
                            little... which I like ;)

                            http://cnczone.com/forums/showthread.php?p=84144#post84144

                            I'm going to try it tomorrow by dangling a couple of bricks off the bench!
                          • Bertho Boman
                            The problem with weight preloading is that you have to accelerate all that extra weight on fast moves and it is not symmetrical. An alternative that avoids the
                            Message 13 of 16 , Mar 1, 2009
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                              The problem with weight preloading is that you have to accelerate all that
                              extra weight on fast moves and it is not symmetrical.



                              An alternative that avoids the mass problem but still works on the same
                              principle is to attach some very long springs. If long enough, there will
                              not be a big difference in the force between the end limits of travel. With
                              some pulleys and ropes to make the arrangement more viable and maybe even
                              bungee cords instead of springs as alternatives.

                              Bertho



                              From: punkrockdad2 Sent: Sunday, March 01, 2009 17:46
                              Looks like you've thought alot of this through already andrew.

                              I've just found this chap whose thinking outside the box just a
                              little... which I like ;)

                              http://cnczone.com/forums/showthread.php?p=84144#post84144






                              [Non-text portions of this message have been removed]
                            • mbonfire2002
                              Or check out constant force springs . www.mcmaster.com has them. Similar in principle to the way a tape measure works. Steve ... all that ... there will ...
                              Message 14 of 16 , Mar 1, 2009
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                                Or check out "constant force springs" . www.mcmaster.com has them.
                                Similar in principle to the way a tape measure works.

                                Steve


                                --- In taigtools@yahoogroups.com, "Bertho Boman" <boman01@...> wrote:
                                >
                                > The problem with weight preloading is that you have to accelerate
                                all that
                                > extra weight on fast moves and it is not symmetrical.
                                >
                                >
                                >
                                > An alternative that avoids the mass problem but still works on the same
                                > principle is to attach some very long springs. If long enough,
                                there will
                                > not be a big difference in the force between the end limits of
                                travel. With
                                > some pulleys and ropes to make the arrangement more viable and maybe
                                even
                                > bungee cords instead of springs as alternatives.
                                >
                                > Bertho
                                >
                                >
                                >
                                > From: punkrockdad2 Sent: Sunday, March 01, 2009 17:46
                                > Looks like you've thought alot of this through already andrew.
                                >
                                > I've just found this chap whose thinking outside the box just a
                                > little... which I like ;)
                                >
                                > http://cnczone.com/forums/showthread.php?p=84144#post84144
                                >
                                >
                                >
                                >
                                >
                                >
                                > [Non-text portions of this message have been removed]
                                >
                              • punkrockdad2
                                Well a couple of large weights later and my x has been reduced to 0.01mm but no immediate improvement on the y as yet. Not quite sure why theres difference.
                                Message 15 of 16 , Mar 2, 2009
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                                  Well a couple of large weights later and my x has been reduced to
                                  0.01mm but no immediate improvement on the y as yet.

                                  Not quite sure why theres difference. Any ideas anyone?



                                  --- In taigtools@yahoogroups.com, "mbonfire2002" <mbonfire@...> wrote:
                                  >
                                  > Or check out "constant force springs" . www.mcmaster.com has them.
                                  > Similar in principle to the way a tape measure works.
                                  >
                                  > Steve
                                  >
                                  >
                                  > --- In taigtools@yahoogroups.com, "Bertho Boman" <boman01@> wrote:
                                  > >
                                  > > The problem with weight preloading is that you have to accelerate
                                  > all that
                                  > > extra weight on fast moves and it is not symmetrical.
                                  > >
                                  > >
                                  > >
                                  > > An alternative that avoids the mass problem but still works on the
                                  same
                                  > > principle is to attach some very long springs. If long enough,
                                  > there will
                                  > > not be a big difference in the force between the end limits of
                                  > travel. With
                                  > > some pulleys and ropes to make the arrangement more viable and maybe
                                  > even
                                  > > bungee cords instead of springs as alternatives.
                                  > >
                                  > > Bertho
                                  > >
                                  > >
                                  > >
                                  > > From: punkrockdad2 Sent: Sunday, March 01, 2009 17:46
                                  > > Looks like you've thought alot of this through already andrew.
                                  > >
                                  > > I've just found this chap whose thinking outside the box just a
                                  > > little... which I like ;)
                                  > >
                                  > > http://cnczone.com/forums/showthread.php?p=84144#post84144
                                  > >
                                  > >
                                  > >
                                  > >
                                  > >
                                  > >
                                  > > [Non-text portions of this message have been removed]
                                  > >
                                  >
                                • punkrockdad2
                                  A little more weight on the y axis was all that was needed. 1st job out today is looking more than perfect. I had to tune the motors down a little to get a bit
                                  Message 16 of 16 , Mar 3, 2009
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                                    A little more weight on the y axis was all that was needed. 1st job
                                    out today is looking more than perfect. I had to tune the motors down
                                    a little to get a bit more torque out of them but I think I was
                                    suffering from Lesters 'closed loop rounded corners' anyway.
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